Note 3 - Summary of Significant Accounting Policies - Remaining Performance Obligations (Details)	Jun. 30, 2021 USD ($)
Revenue, Remaining Performance Obligation, Amount	$ 3,906,000
Service [Member]
Revenue, Remaining Performance Obligation, Amount	2,224,000
Clinical Revenue [Member]
Revenue, Remaining Performance Obligation, Amount	205,000
Exclusivity Fee [Member]
Revenue, Remaining Performance Obligation, Amount	$ 1,477,000